Commercial laundries handle large volumes of a variety of materials, including table cloths, napkins and other table linens used in restaurants and other food service operations. Uniforms worn by manufacturing and service personnel and others are examples of other types of articles that are typically laundered by commercial laundries. A significant part of the operation of commercial laundries involves sorting the different types of articles while keeping track of where they came from and the number and types of articles that are to be laundered.
Typically, the items are sorted at a sorting table or other sorting station. Like articles are then conveyed pneumatically to another location where they are further handled. Because flexible fabrics tend to ball up when pushed through pneumatic conveyor tubes, they are usually pulled through the tubing system by suction. The type of system that is most prevalent in commercial laundries makes use of vacuum bins that are each provided with a large vacuum motor. The vacuum that is applied to the vacuum bins pulls the laundry items through the conveyor tubes and into the bins.
Although vacuum bins of this type have achieved considerable popularity, they have not been satisfactory in all respects. Their relatively high cost adds appreciably to the capital costs of the laundry equipment. Furthermore, it is necessary for the items in the vacuum bins to be dumped onto a belt conveyor which carries them to the location of receptacles that are typically flexible carts commonly referred to as sling carts. From there, the slings must be weighed for proper wash load weight before being hoisted onto an overhead monorail. The articles must then be manually unloaded from the conveyor and placed in the sling carts. As can easily be appreciated, the need for all of these manual operations adds significantly to the overall labor costs. Finally, the vacuum bins and conveyors that transport articles from the bins to the sling carts occupy considerable space. This is particularly unsatisfactory in the case of commercial laundries because they are usually located in high cost urban areas where they are close to their major customers.